This is a note to let you know that I've just added the patch titled mailbox: PCC: handle parse error to the 4.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mailbox-pcc-handle-parse-error.patch and it can be found in the queue-4.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From afd0b1fb22269f48d68fdf269891c653818c8047 Mon Sep 17 00:00:00 2001 From: David Arcari <darcari@xxxxxxxxxx> Date: Mon, 27 Aug 2018 15:19:08 -0400 Subject: mailbox: PCC: handle parse error From: David Arcari <darcari@xxxxxxxxxx> commit afd0b1fb22269f48d68fdf269891c653818c8047 upstream. acpi_pcc_probe() calls acpi_table_parse_entries_array() but fails to check for an error return. This in turn can result in calling kcalloc() with a negative count as well as emitting the following misleading erorr message: [ 2.642015] Could not allocate space for PCC mbox channels Fixes: 8f8027c5f935 (mailbox: PCC: erroneous error message when parsing ACPI PCCT) Signed-off-by: David Arcari <darcari@xxxxxxxxxx> Reviewed-by: Al Stone <ahs3@xxxxxxxxxx> Cc: 4.18+ <stable@xxxxxxxxxxxxxxx> # 4.18+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/mailbox/pcc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/mailbox/pcc.c +++ b/drivers/mailbox/pcc.c @@ -461,8 +461,11 @@ static int __init acpi_pcc_probe(void) count = acpi_table_parse_entries_array(ACPI_SIG_PCCT, sizeof(struct acpi_table_pcct), proc, ACPI_PCCT_TYPE_RESERVED, MAX_PCC_SUBSPACES); - if (count == 0 || count > MAX_PCC_SUBSPACES) { - pr_warn("Invalid PCCT: %d PCC subspaces\n", count); + if (count <= 0 || count > MAX_PCC_SUBSPACES) { + if (count < 0) + pr_warn("Error parsing PCC subspaces from PCCT\n"); + else + pr_warn("Invalid PCCT: %d PCC subspaces\n", count); return -EINVAL; } Patches currently in stable-queue which might be from darcari@xxxxxxxxxx are queue-4.18/mailbox-pcc-handle-parse-error.patch